Well, I had some work done on the car over the last few days. The good news: Just got a call that the work is done! The bad news: The shop was nice enough to fill my tank with what I'm assuming is 87 octane. The car currently has an 89 tune on it and I do not have an 87 to replace it with. I have a call in to AM but given the nasty state of the weather on the east coast, I don't expect a resolution today.

Do I have any concerns running the car at a lower octane? I'd say the tank was about 1/4 full when it was filled (so the mix is around 1/4 89 and 3/4 87.

Thanks in advance

 

Just keep your foot out of it until you can get some good fuel in there

 

If you hear detonation / pinging siphon the gas out and put it in the lawn mower. Now go get a tank of real fuel. Good Luck

 

Ouch. I'd be very careful with this. Either retune it for 87 and burn it up or try to get rid of that gas asap. Never put lower octane with a higher octane tune. Any damage done should fall on the shop.

 

If you can't temporarily re-tune, just go easy on the car as long as you don't hear knocking / pinging. How much 89 octane fuel was in the tank before they filled it up? If you were at half, then burn off 1/4 of a tank and top off with 93 octane. It's not exact math but it will get you closer to where you should be.

 

Since this post is 7 months old, I would assume he has used up that tank of gas.